Clinical Topics: Infectious Disease

Inland bearded dragons are native to Australia and are a popular companion animal. Private breeders often select for desirable temperaments and various color morphologies in an effort to provide an ever-increasing variety to the pet trade. They are also bred commercially and sold by large pet retailers making them a widely available pet reptile…

The “Pigeon Disease Primer” explores important differential diagnoses for common clinical problems observed in pigeons and doves. Although the clinical approach to the columbiform relies on the same concepts of “One Medicine” used in all species, many of the infectious diseases of pigeons are relatively unique to this taxonomic group, or at least much more prevalent when compared to psittacine birds or songbirds.

Did you attend the Lafeber Symposium at the 2015 International Conference on Avian heRpetological and Exotic mammal medicine in Paris? View a recording of this encore, web-based seminar: “Medical Management of Psittacines with Bornavirus Ganglioneuritis (PDD)” by Susan Orosz, DVM, DABVP (Avian Practice), DECZM (Avian). This presentation on avian borna virus contains medium to advanced level content. The novice is encouraged to view the first hour of Dr. Orosz’s presentation “Anatomy & Physiology of the Avian Gastrointestinal Tract: Clinical Applications”, which includes a helpful review of avian gastrointestinal anatomy and physiology.

Red leg syndrome, also known as “pink belly disease” or bacterial dermatosepticemia, is one of the most common clinical conditions of captive frogs. Associated with peracute to acute bacterial septicemia, red leg is generally a disease of captive animals although the condition has also been implicated in rare mass mortalities of wild amphibians. This presenting problem article reviews clinical findings in red leg syndrome, pathogenesis of disease, as well as key points of urgent care and prognosis. The basics of case management are then reviewed: differential diagnoses, diagnostics, treatment, prevention and control.

The non-hyphal, zoosporic, chytrid fungus Batrachochytrium dendrobatidis (Bd) has caused widespread and dramatic population declines in both wild and captive amphibians worldwide. Use this table to review the basics of the infectious disease chytridiomycosis

Proventricular dilatation disease or PDD is one of the most frustrating avian conditions encountered today. The recent discovery of a causal relationship between PDD and avian bornavirus has not simplified the challenges that are faced. The detection of avian bornavirus infection is common in birds with PDD but is also detected in birds with other chronic diseases that are not diagnosed with PDD. Proventricular dilatation disease was first reported in the late 1970s…

Neurologic diseases are relatively common in companion rabbits, and recognition of these conditions by the exotic animal clinician is very important. Encephalitozoonosis is endemic in the pet rabbit population worldwide, and is an important cause of neurologic disease in this species.

Quarantine is a basic component of good preventive medicine. The purpose of quarantine is to protect both the existing collection and the new arrival. New birds are usually stressed and may be more susceptible to infectious diseases. The quarantine period also allows the new bird(s) to acclimate to its new environment, food, and owner. Proper client education is paramount to minimize and/or eliminate the risk of infectious disease outbreaks.

Fungi are among the most common causes of infectious disease in captive birds, and fungal diseases can be challenging to diagnose, as well as treat. Because fungi are typically opportunistic, causing non-contagious disease in susceptible individuals, prevention and treatment require an understanding of etiology as well as predisposing factors.

Psittacosis or ornithosis is caused by Chlamydophila psittaci, an obligate intracellular bacterial infection of birds. Chlamydophila psittaci may be excreted in feces and oculonasal discharge. Chlamydophila is environmentally labile but remains infectious for months in organic debris. Latently infected birds appear healthy but shed the organism intermittently for months to years. Stressors such as breeding, shipping, crowding, or climatic extremes may activate shedding.

The first step in antimicrobial drug selection is to make sure treatment is necessary. Companion birds often display nonspecific signs of illness, and the avian clinician should be reasonably sure that an infection is present before using antibiotics. The presence of a pathogen on culture or Gram stain does not necessarily mean treatment is warranted. Small numbers of potential pathogens are frequently isolated from the choana and cloaca of healthy birds.

Diarrhea is the most common problem in pet hamsters. In a recent survey of two large American commercial breeding facilities, approximately 3% of shipped hamsters develop diarrhea. Diarrhea caused by enterocolitis can occur in hamsters of any age or breed and is commonly known as “wet-tail”. Clinical signs in weanlings usually include diarrhea, anorexia, ruffled hair, dehydration, weight loss, and death. The mortality rate is often highest in…

The large size of the raptor eye and its relative lack of orbital protection superiorly and laterally means any form of head trauma frequently involves the eye and its associated structures. In one report, ocular injuries were most commonly caused by vehicular collision, gunshot and leghold traps. The most common clinical finding in birds of prey presented for medical attention is hyphema. Trauma may also lead to…

An average 250 human cases of Chlamydophila psittaci are reported annually in the United States. Clinical signs typically follows a 5 to 14 day incubation period. Disease ranges from subclinical to systemic illness with severe pneumonia. Most people demonstrate sudden onset fever, headache, malaise, and myalgia with a non-productive cough that can be accompanied by breathing difficulty and chest tightness. Splenomegaly and…

The ferret is a carnivore with a short, simple gastrointestinal tract and a relatively rapid gastrointestinal transit time. Diarrhea is the most common clinical sign in ferrets with gastrointestinal disease, with the exception of gastrointestinal foreign bodies where anorexia and weight loss are the primary presenting complaints.

Rhinitis or sinusitis, sometimes called “snuffles” in laymen’s terms, is usually characterized by unilateral or bilateral, mucopurulent nasal discharge, sneezing, and congestion. A subtle sign of upper respiratory tract disease can be discharge matted on the paws or the medial aspect of the forelimbs. Discharge may collect here as the rabbit fastidiously cleans its face with its forepaws. In the early stages of disease, discharge may not be evident on the nose or even on the paws, however close examination of…

The most common presentation of P. multocida infection is upper respiratory tract disease. Pasteurella multocida was identified as a cause of mucopurulent rhinitis in rabbits or “snuffles” in the 1920s. Clinical signs include mucopurulent nasal discharge, sneezing, congestion, and/or snoring. Infection of the nasolacrimal duct may extend to the conjunctiva causing ocular discharge and nasolacrimal duct obstruction. Affected rabbits may also have…

Most species of mites are host-specific, however take special precautions, such as wearing exam gloves, to minimize the spread of potentially zoonotic pathogens. Humans that become infested with Sarcoptes scabei may develop wheals, vesicles, papules, and intense pruritus. Pet owners, especially children, may become infected with…

Although fungal disease is uncommon in small mammals, dermatophytosis is the most common mycosis seen in clinical practice. Despite the low incidence of clinical disease, rodents are common asymptomatic carriers of dermatophytes. Fungal pathogens are generally more important for their zoonotic potential. Rodents are frequently asymptomatic carriers of ringworm, and transmission of disease to human caretakers is not uncommon.

It’s flu season! Ferrets are susceptible to several strains of human influenza virus, which is spread through the air from coughing, sneezing, and other respiratory secretions. Provided by Dr. Connie Kirk, this client education handout describes the signs of flu in the ferret as well as preventive measures to reduce the risk of illness.

The physical and psychological benefits of pet ownership have been well established, however pet ownership is not without risks such as the potential for transmission of zoonotic disease. Reptiles can carry a number of bacterial, fungal, protozoal, and parasitic pathogens including Salmonella spp. Approximately 6% of human Salmonella spp. infections are acquired from reptiles.

Disseminated idiopathic myofasciitis (DIM) is a severe inflammatory disease that primarily affects skeletal, smooth, and cardiac muscles as well as surrounding connective tissues. This recently identified disease typically affects young ferrets, less than 18 months of age. The cause of DIM is unknown, but this condition is suspected to be an acquired immune-mediated disease. The onset of DIM is usually acute to subacute, followed by a rapid decline over 12-36 hours. The most prominent clinical signs include a high fever ranging from…

Clinical signs of upper respiratory tract disease in the ferret can include congestion, sneezing, oculonasal discharge, and non-specific signs of illness, such as reduced appetite, lethargy, and weight loss. If disease extends lower into the respiratory tract, cough, tachypnea, and…

Tularemia is a highly pathogenic disease of animals and humans that has been reported throughout the northern hemisphere including North America, Europe, and Asia. In the United States, naturally occurring infections have been reported in all states except Hawaii.

The physical and psychological benefits of pet ownership have been well established, however close contact with pets is not without risks including the potential for transmission of zoonotic disease. Rodents can carry a number of potential pathogens including lymphocytic choriomeningitis virus. Lymphocytic choriomeningitis virus is found throughout the world in wild rodents. Disease is especially common in…

Head tilt or torticollis, also known as “wry neck”, is a common emergency presentation of the pet rabbit. There are many other potential causes of head ataxia including: otitis externa, cerebral larval migrans caused by Baylisascaris procyonis, listerioisis, toxoplasmosis, rabies virus infection or other conditions affecting the central nervous system such as trauma, lead toxicity, or neoplasia.

More than 200 diseases are zoonotic or common to animals and humans. Veterinary staff members are continually exposed to animals that potentially carry infectious disease. This risk is an acceptable one as long as the risk is known, understood, and preventive measures are taken. These preventive measures are fairly straightforward and include…

It is important for animal health care professionals to recognize the potential hazards of working with passerine birds so that appropriate measures can be taken to minimize the risk of contracting disease. Wild bird isolates of Salmonella enterica serotype typhimurium may not represent a large zoonotic risk to the general population, however the vast majority of sick and dying songbirds harbor this microbe.

Signs of avian polyomavirus type 1 in the budgerigar parakeet can be quite variable. Feather dystrophy or abnormal feather growth can lead to deformed flight feathers. Affected birds are unable to fly and are called “runners” or “creepers”. “French molt” is a term sometimes used for this slow, debilitating disease in parakeets characterized by progressive development of abnormal feathers. Bleeding is another hallmark of clinical avian polyomavirus infection…

Bite wounds are not confined to small animal practice. Bite wounds are a common and significant problem in clinical practice, and LafeberVet’s presenting problem article features urgent care tips for this universal problem of veterinary patients. The incidence of bite wounds increases with a history of exposure to the outdoors or to other animals. The owner may even report a fight or interaction that results in a bite wound.

Unlike many waterfowl species, Canada geese tend to travel further from water to feed. In turn, this allows birds to spread their feces over large areas. While feeding, one Canada goose can produce approximately one dropping per minute. Total daily fecal production may reach approximately 2 pounds or more of waste per goose.

Approach to the passerine bird relies on the same concepts of “One Medicine” used in all animals. Nevertheless many of the infectious agents diagnosed in songbirds are relatively unique to this taxonomic group, or at least much more prevalent when compared to psittacine birds or birds of prey.

Lymphoid leukosis and Marek’s disease virus are two diseases of the avian leukosis complex. These conditions are commercially important diseases of poultry seen worldwide. Lymphoid leukosis and Marek’s disease were the first neoplastic diseases shown to be transmitted and caused by viruses…

Order Galliformes consists of heavy-bodied, ground feeding birds like the chicken, turkey, quail, and pheasant. Backyard or hobby flocks consist of meat and game birds; or ornamental or show birds. Conditions commonly encountered in backyard chickens and turkeys often include endoparasites like Eimeria spp., pasteurellosis or fowl cholera, mycoplasmosis, staphylococcosis, and colibacillosis. Another common presenting problem is trauma, which can typically be categorized as…

Although the rare veterinarian routinely deals with large numbers of waterfowl on a regular basis, many avian veterinarians encounter waterfowl only sporadically as wildlife rehabilitation cases, backyard poultry, and/or zoo specimens. When consulting textbooks for help, often a dizzying array of waterfowl diseases are encountered. Some conditions such as “angel wing” and predator trauma are important in captive populations, while infectious diseases like fowl cholera can cause massive die-offs in free-ranging birds…

This case study is based on a report prepared by Veterinary Answers Consultant, Gwen Flinchum, DVM, Dipl. ABVP (Avian). A 5-year old female umbrella cockatoo is presented for lethargy, open-mouthed breathing, and difficulty gripping of 2-3 days duration.

Donated by Dr. Eric Klaphake, this client education handout describes psittacine beak and feather disease (PBFD), an important disease of parrots. This handout discusses the cause of PBFD, bird species at greatest risk, transmission, as well as diagnosis or testing. Recommendations for removal of PBFD from a collection or aviary are also described.

The turtle ear is a simple structure that sits caudoventral to the eye covered by a large scale called the tympanic scute. As in many reptiles, the external ear is absent in chelonians. The tympanic membrane sits flush against the skin just underneath the tympanic scute. There is one ossicle, the columella, which crosses the large tympanic cavity to insert medially on the oval window of the cochlea. A narrow Eustachian tube connects the middle ear to the oropharynx.

Aural abscesses are well-encapsulated, caseous plugs that slowly develop until it fills the tympanic cavity. The cause of aural abscessation is not completely understood…

All mammals are considered to be susceptible to rabies although susceptibility appears to vary by species and viral variant. Rabies is exceedingly rare among small wild mammals and exotic pets. Among rodents in the United States, rabies is most commonly reported in…

Stomatitis, also known as “mouth rot”, ulcerative stomatitis, necrotic stomatitis, and/or periodontal disease is a common problem in snakes and lizards. Stomatitis is less common in chelonians and crocodilians, and often presents as a stomatitis-rhinitis complex in tortoises. This presenting problem article explores the pertinent anatomy involved, key points of urgent care, as well as tips for case management.

In My Experience: Living with a PDD Bird was authored by a diligent parrot owner and reviewed by her avian veterinarian. This commentary includes suggestions on diet as well as management tips that improved the quality of life, and possibly the life span, of this owner’s birds.

Electrophoretic patterns among avian species have been found to be quite different from those seen in mammals. The protein electrophoresis patterns of psittacine species that have been studied generally include the presence of prealbumin in many species, lower normal concentrations of gamma-globulin, and increases in the…

Avian polyomavirus infection is a disease in psittacine birds or parrots of greatest concern in chicks. This client handout briefly explains this important disease from signs and transmission to diagnostic testing and control or prevention.